Dehydration of Ethylene Glycol Monoethyl Ether to Ethyl Vinyl Ether over K₃PO₄/SiO₂ Catalyst: the Effect of Surface Acid–Base Properties

This research introduces a sustainable method for synthesizing vinyl ether alkyl compounds through the gas-phase dehydration of coal-based ethylene glycol monoethyl ether (EGEE) over a silica-supported potassium phosphate (K3PO4/SiO2) catalyst. Under optimized conditions of 440 °C, 1 atm pressure, and a weight hourly space velocity (WHSV) of 0.56 h–1, the 5K3PO4/SiO2 catalyst achieved an EGEE conversion of 88% and an ethyl vinyl ether (EVE) selectivity of 76%. Characterization techniques including X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, thermogravimetric analysis (TGA), temperature-programmed desorption (TPD), inductively coupled plasma (ICP), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) revealed that the exceptional performance of the K3PO4/SiO2 catalyst is attributed to its well-balanced surface acid–base properties, which are critical for the efficient dehydration of EGEE to EVE.